Syfy's Krypton has cast Game of Thrones alum Hannah Waddingham in the recurring role of Jax-Ur, a character from DC Comics' Superman lore.

Although Jax-Ur previously appeared on Superman: The Animated Series and in 2013's Man of Steel, this will be the first time the character has been portrayed by a woman.

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Introduced in 1961 in Action Comics #289, Jax-Ur was an amoral Kryptonian scientist sentenced to the Phantom Zone for mass murder after he destroyed an inhabited moon while testing a rocket equipped with a nuclear warhead. He occasionally escaped from that prison dimension, and even once helped the Man of Steel. Jax-Ur has appeared in comics in more recent years, where he was depicted as one of General Zod's "sleeper Kryptonians" living on Earth and then, during DC's New 52, as a Phantom Zone criminal who as a young military officer was once the partner and fiancé of Superman's biological mother.

Hannah Waddingham
Hannah Waddingham

On Krypton, Jax-Ur was once one of the planet's greatest scientists who's now determined to bring about radical change as leader of the underground terrorist organization known as Black Zero. In DC Comics canon, post-Crisis on Infinite Earths, Black Zero was originally part of the larger "clone liberation movement," and bore ultimate responsibility for the destruction of Krypton. More recently, it was the name of of an elite Kryptonian military force.

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Developed by David S. Goyer and Damian Kindler, Krypton is set two generations before the destruction of Superman's home planet. The drama follows the Man of Steel's grandfather Seg-El (Cameron Cuffe), whose encounter with Earthly time traveler Adam Strange (Shaun Sipos) changes his life, and the course of history.

Waddingham has appeared on Syfy's 12 Monkeys and BBC's The Club, but she's undoubtedly most familiar for her role as Septa Unella, aka the "shame" nun, on HBO's Game of Thrones.

Debuting March 21 on Syfy, Krypton stars Cameron Cuffe, Georgina Campbell, Elliot Cowan, Ann Ogbomo, Rasmus Hardiker, Wallis Day, Aaron Pierre and Ian McElhinney.